叶用银杏半同胞家系苗期性状生长动态及苗期选择

对银杏2年生苗苗高、地径生长过程运用Logistic方程进行模拟，相关系数均在0．97以上，银杏高生长在萌芽展叶后直接进入速生期，地径生长速生期开始与结束均要晚于苗高生长速生期，不同家系苗高、地径生长速生期的停止期差异较大。银杏苗期叶片的叶长、叶宽、单叶干重、单叶鲜重、平均单叶面积等形态指标的年生长节律呈S型曲线、内含物的年变化规律呈双峰型曲线。研究表明：苗高与地径生长的速生期终点、成熟健康叶片的叶面积、9月初的叶片总内酯含量、9月底的叶片总黄酮含量等性状可作为叶用银杏家系苗期选择的重要指标。

Seedling Growth Dynamics in Half-sib Ginkgo Families with Reference to Seedling Selection

The growth in height and root collar diameter in tw o-year-old ginkgo seedlings is simulated with the Logistic equation, and the c orrelational coefficients are all above 0.97. Whatever the family, the height gr owth enters the rapid growing phase directly after the leaf spread, but comes to a close at times differing from one family to another. With the root collar dia meter, the start and end of the rapid growing phase are both later than the heig ht, and the ending time also varies with the family. While the annual growth cur ves of such morphological leaf traits as the length, width, dry weight, fresh we ight, and mean leaf area are S-shaped, the annual changing pattern of the leaf extracts is of double-peak curves. It is concluded that the ending time of the fast growing phase in height and root collar diameter, the leaf area of mature a nd healthy leaflets, the content of total leaf ginkgolides at early September, a nd the content of total leaf flavone at late September can all be helpful trait indices in the selection of seedlings.